There have conventionally occurred crimes that a foreign matter is set in a card traveling path in a card reader such as an ATM (automated teller machine) or the like to steal other people's cards in order to illegally use them.
Although means for, e.g., detecting a foreign matter in the card traveling path is provided against such crimes, there is a system like a card reader disclosed in, e.g., U.S. Pat. No. 5,850,079 that a cutting edge is provided at an end of a shutter plate and a foreign matter such as a card trap member is cut.
In case of a structure that the card trap member is cut by the shutter plate like this card reader, however, the card may be damaged when the cutting edge is brought into contact with the lower surface of the card.
Further, Japanese patent application laid-open No. 272922/1996 discloses a foreign matter insertion detection mechanism (U.S. Pat. No. 3,035,725) which detects whether a foreign matter has been inserted by using a scanning member which scans an entire lateral widthwise area of a traveling path. Such a detection mechanism performs foreign matter detection in a state that the card is not taken into the card reader, i.e., that there is no card in the card traveling path because of the structure that the scanning member scans the entire lateral widthwise area of the traveling path.
In such a foreign matter insertion detection mechanism, however, even in the case that the card is inserted and taken into the card reader as well as the case that no card is provided, the detection capability can be further improved as long as a foreign matter can be detected, which is preferable in view of enhancement of the security property of the card reader.
Furthermore, in conventional card readers, there has been widely used a base which has an information recording medium or a recording head attached thereto or mounted thereon and can move in predetermined direction (in this specification, such a base which moves with a given object attached thereto or mounted thereon is referred to as a “carriage”).
As adopted in an apparatus disclosed in, e.g., Japanese patent application laid-open No. 42068/1993, such a carriage movement mechanism used to move a carriage is generally constituted by a slide shaft 102, a guide member 103 which restricts rotation of a carriage 101, and a drive belt 104 such as shown in FIG. 12.
Furthermore, like an apparatus disclosed in, e.g., Japanese patent application laid-open No. 31867/1995, guiding and rotation restriction of a carriage 101 are performed by two shafts while the carriage 101 is reciprocated by rotating a drive belt 104 in one direction.
In such a carriage movement mechanism, however, since the slide shaft 102, the guide member 103, the drive belt 104 and others require a large space, this mechanism cannot be utilized in a small apparatus in some cases. In particular, when the slide shaft 102 and the guide member 103 are arranged on the both sides of the carriage 101, a larger space may be required in some cases, thereby complicating minimization.
It is, therefore, an object of the present invention to provide a foreign matter detection mechanism which can cut or detect a foreign matter without damaging a card surface. Moreover, it is another object of the present invention to provide a foreign matter detection mechanism which can detect a foreign matter in a card reader irrespective of presence/absence of a card. In addition, it is still another object of the present invention to provide a carriage movement mechanism which is advantageous for minimization and a method for operating the carriage movement mechanism.